By 1863, the Confederate hold on the Mississippi River was limited to Vicksburg and Port Hudson- both strong bastions- difficult to overcome. In a daring move, U. S. Grant, commanding the Union forces, sent his troops past Vicksburg and landed to the south of the city. Grant's troops then defeated Confederate forces in five separate engagements. After a 6 week seige, Confederate forces surrendered.
To the Confederates Vicksburg was there 'Gibraltar of the West', it together with Port Hudson were the only two points that the South held on the Mississippi. Grant had tried a number of round-about approaches to Vicksburg including the building of a by pass canal, as well various routes through the bayous. Finally, Grant decided on the direct approach. He sent his army south of Vicksburg on the opposite side of the river. Then he sent his gunboats and a number of transports south passed the guns of Vicksburg to ferry the troops across the mile wide Mississippi. On April 16 th three transports and eight gunboats traversed the guns of Vicksburg.
Despite the fact that defenders of Vicksburg fired 525 rounds at them, they succeeded in making it past the guns with the lose of only one transport. A few days later additional boats followed. To confuse the confederate defenders commanded by General Pemberston, Grant sent Union cavalry men under the command of Benjamin Grierson to raid the Confederate interior. His raid was highly successful. He successfully crossed the state of Mississippi, destroying railroads and other materials, while avoiding his pursuers.
The great success of the raid was however, in forcing Pemberston to detach troops to follow him. Grant also detached a division of Sherman troops to feint an attack North of the city. This causes Pemberston to send troops guarding the Southern approaches to the North. Thus when Grant crossed with all of his forces he was not opposed. Once across instead of attacking Vicksburg, Grant moved eastward towards Jackson the state capital. There, Confederate General Johnson was putting together a forces to oppose Grant.
Grant's forces quickly overwhelmed the confederates in Jackson. In four additional battles Grants forces totally decimated Confederate forces. After defeating all of the field armies that he faced, Grant then attacked Vicksburg itself on May 19 th. He failed in the first attack which he followed up with a second, which also failed. Finally, Grant settled down for a siege of the city. After six weeks, of deprivation, and in the face of a planned Union assault, the Confederates surrendered.
Grant paroled all of the Confederate soldiers. A few days later when the news of Vicksburg surrender reached Fort Hudson, it too surrendered. Thus is one of the most successful campaigns of the Civil War Grant had cleared the Mississippi of Confederate forces.